Noiʻi no ke kūʻē ʻino ʻana o ka ʻili Galvalume wela

Ua hoʻohana nui ʻia nā uhi galvalume Zn55Al1.6Si wela i nā ʻano he nui e like me ka ʻoihana kaʻa, ka hana moku, nā ʻoihana mīkini a me nā mea ʻē aʻe, ʻaʻole wale i kāna hana anti-corrosive ʻoi aku ka maikaʻi ma mua o ka Zinc coating, akā i kona kumukūʻai haʻahaʻa. Ua emi iho ke kumu kuai o Al i ko Zn i keia manawa). Hiki i nā ʻāina laha ʻole e like me La ke keʻakeʻa i ka ulu ʻana o ka unahi a hoʻonui i ka pili ʻana o ka unahi, no laila ua hoʻohana ʻia lākou e pale i nā kila a me nā mea ʻē aʻe. ke kino nā huila e kūʻē i ka oxidation a me ka corrosion. Eia naʻe, he kakaikahi wale nō nā puke i paʻi ʻia e pili ana i ka hoʻohana ʻana i ka La i loko o ka uhi galvalume wela, a ma kēia pepa ua noiʻi ʻia nā hopena o ka hoʻohui La i ke kūpaʻa ʻino o ka uhi galvalume wela.

Hoʻokolohua

[1] Luʻu wela

Hoʻokomo ʻia nā mea hoʻopili wela Zn-Al-Si-La i loaʻa ka 0,0.02wt.%, 0.05wt.%, 0.1wt.% a me 0.2wt.% La ma Ф 1 mm uea kila māmā. Penei ke kaʻina hana: hoʻomaʻemaʻe e wehe i ka ʻōpala a me ka hamo ʻia e ka nalu supersonic (55 °C) → hoʻomaʻemaʻe me ka wai → fluxing (85 °C) → hoʻomaloʻo (100 ~ 200 °C) wela-luʻu (640 ~ 670 °C, 3～5 s).

[2] Ho'āʻo pohō kaumaha

Ua ana ʻia ka hoʻāʻo pohō kaumaha e ka copper-accelerated acetic acid salt spray testing (CASS) a me ka hoʻāʻo ʻana i ka corrosion immersion i hana ʻia i loko o ke keʻena paʻakai a me 3.5% NaCl solution. Ma hope o ka hoʻāʻo ʻana, ua hoʻoneʻe ʻia nā huahana corrosive e nā ʻano mechanical, holoi ʻia me ka wai kahe, a laila hoʻomaloʻo ʻia e ka ea anuanu a me ka pohō kaumaha i ana ʻia e ka ʻelepona uila. Ma na hihia elua, ekolu paralUa hana ʻia nā laʻana lel no ka loaʻa ʻana o nā hopena pololei. ʻO ka manawa hoʻāʻo he 120 mau hola no ka hoʻāʻo CASS a me 840 mau hola no ka hoʻāʻo ʻana.

[3] Ho'āʻo ʻeleka

Ua lawe ʻia ka hoʻāʻo electrochemical e IM6e electrochemical work station i hoʻolako ʻia e Kelemania, e lawe ana i ka platinum plate ma ke ʻano he counter electrode, saturated calomel electrode e like me ka electrode kuhikuhi, a me ka Zn-Al-Si-La i hoʻopaʻa ʻia i ka wela me ka uea kila māmā e like me ka electrode hana. He 3.5% ka hopena NaCl ka mea hoʻoheheʻe. ʻO 1cm2 ka ʻāpana ili i ʻike ʻia i ka hopena hoʻāʻo. Electrochemical impedance spectroscopy (EIS) nā ana me ka alapine i hele mai ka 10 kHz a hiki i ka 10 mHz, ka laula o ka sinusoidal voltage hōʻailona he 10 mV (rms) .Weak polarization curves i hoʻopaʻa 'ia ma ka voltage range mai -70 mV. i ka 70 mV, ʻo ka helu scanning he 1 mV/s. Ma nā hihia ʻelua, ʻaʻole i hoʻomaka ka hoʻokolohua a hiki i ka paʻa ʻana o ka hiki ʻana o ka corrosion (kahi hoʻololi o lalo o 5 mV i 5 min).

[4] Haʻawina SEM a me XRD

Ua nānā ʻia nā morphologies ʻili o nā laʻana e ka SSX-550 scanning electron microscope (SEM) ma hope o ka hoʻāʻo ʻana i ka corrosion i loko o ke keʻena paʻakai a me 3.5% NaCl solution. Ua hoʻāʻo ʻia nā huahana corrosion ma luna o ka ʻili o nā laʻana i loko o ka paʻakai paʻakai a me 3.5% NaCl solution me ka hoʻohana ʻana i ka PW-3040160 X-ray diffraction (XRD).

Nā hualoaʻa a me ka kūkā

[1] Kūʻē ʻino
[1.1] Ke poho kaumaha
Hōʻike ka Fig.1 i nā hopena o nā ho'āʻo hoʻemi kaumaha i loko o ke keʻena paʻakai paʻakai a me ka solution 3.5% NaCl. Ua emi mua ka nui o ka corrosion o na la'ana ma na hihia elua me ka hoonui ana i ka maona La a hiki i ka 0.05wt.% a laila mahuahua me ka hoomahuahua ana i ka maona La. No laila, ua ʻike ʻia ke kūpaʻa corrosion maikaʻi loa i nā uhi i loaʻa ka 0.05wt.%La. Ua ʻike ʻia i ka wā o ka hoʻāʻo ʻana, ua ʻike mua ʻia ka ʻula ʻulaʻula ma ka 0wt.%La i uhi ʻia ma ka 3.5% NaCl solution, akā naʻe, a hiki i ka pau ʻana o ka hoʻāʻo ʻana, ʻaʻohe ʻula ʻulaʻula ma ka 0.05wt.% La uhi ʻili. .

2.1.2 Electrochemical ho'āʻo

Hōʻike ka Fig.2 i nā pihi polarization nāwaliwali no nā ʻāpana ʻāpana Zn-Al-Si-La i loko o 3.5% NaCl solution. Hiki ke ʻike ʻia ke ʻano o nā ʻāpana polarization nāwaliwali i hōʻike ʻia i nā ʻokoʻa liʻiliʻi, a ua hoʻomalu ʻia ke kaʻina hana corrosion o kēlā me kēia ʻano o nā mea hoʻoheheʻe ʻia e ka cathodic reaction. Hōʻike ʻia nā hopena kūpono ʻo Tafel e pili ana i nā pihi polarization nāwaliwali ma Fig.2 i ka Papa 1. E like me ka hoʻāʻo ʻana i ke kaumaha, ua ʻike pū ʻia e hiki ke hoʻomaikaʻi ʻia ke kūpaʻa corrosion o ka uhi galvalume e ka hoʻohui liʻiliʻi o La a me ka liʻiliʻi loa. ua loaʻa ka nui o ka corrosion me 0.05wt.%La.

Hōʻike ka Fig.3 i nā kiʻi Nyquist i hoʻopaʻa ʻia no nā uhi me nā nui like ʻole o ka hoʻohui La i hōʻike ʻia i 3.5% NaCl solution no 0.5 h. I nā hihia a pau, ʻelua mau arcs ʻo ia ka manaʻo o ʻelua mau manawa mau. ʻO ka mea i ʻike ʻia ma ke alapine kiʻekiʻe e hōʻike ana i ke ʻano dielectric o ka uhi ʻana, ʻoiai ʻo ka mea ma ke alapine haʻahaʻa e pili ana i ka substrate kila māmā i loko o nā pores (ʻo ia hoʻi nā defects Coating). I ka hoʻonuiʻana o ka La, ua hoʻonuiʻia ke anawaena o ke alapine kiʻekiʻe, uaʻoi aku ka manaʻo o kēia hopena ma keʻano o ka Zn55Al1.6Si0.05La alloy coating. Me ka hoʻonui hou ʻana i ka ʻike La, akā naʻe, ua emi ke anawaena o ke alapine kiʻekiʻe. I kēia manawa, hilinaʻi ke kikowaena o nā arcs a pau i ka quadrant ʻehā, e hōʻike ana i ka hopena dispersion ma luna o ka electrode surface. Ma lalo o kēia kūlana, hiki ke loaʻa nā hopena maikaʻi aʻe ma ka hoʻohana ʻana i ka CPE (constant phase element) ma kahi o ka capacitance maʻemaʻe i hōʻike ʻia e. hui noiʻi ʻē aʻe.